Diaphragm Pump and Motor System and Method

ABSTRACT

Embodiments of the invention provide a pump assembly including a pump, a motor, and a baseplate. The pump includes a valve housing and an upper housing with a ring to separate an inlet chamber from an outlet chamber. An o-ring is positioned between raised outer walls of the ring and secured by a cutout of the valve housing. The motor includes a brush ring assembly with brush holders and torsion springs urging brushes through the brush holders. The baseplate includes a cutout capable of allowing the use of a clamp or a wrap to couple the baseplate to the motor.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §119 to U.S. Provisional Patent Application No. 61/425,696 filed on Dec. 21, 2010, the entire contents of which is incorporated herein by reference.

BACKGROUND

Wobble-plate pumps typically include pistons that move in a reciprocating manner within corresponding pump chambers. In many cases, the pistons are moved by a surface of a wobble plate that is rotated by a motor or other driving device. The reciprocating movement of the pistons pumps fluid from an inlet chamber to an outlet chamber of the pump.

Many conventional pumps include a valve housing with inlet and outlet valves that allow fluid in and out of the pump chambers in response to the reciprocating movement of the pistons. The inlet and outlet valves are often press-fitted into the valve housing. However, at high pressures and high viscosities, valves have a tendency to balloon, spin, or pop out of the valve housing, greatly reducing the efficiency of the pump and requiring maintenance to be performed on the pump. In addition, at high pressures and high viscosities, the valve housing has a tendency to wobble within the pump, causing unnecessary wear on the o-ring that helps seal the inlet and outlet chambers.

Many conventional pumps are also coupled to baseplates or pedestals to support the weight of the pump and a corresponding motor. The baseplate or pedestal usually has a small base coupled to the motor via mounting holes and fasteners and legs extending from the base to allow the pump and motor assembly to sit on or be coupled to a flat surface.

SUMMARY

Some embodiments of the invention provide a pump assembly including a pump, a motor, and a baseplate. The baseplate extends across a length of the motor and includes a base, legs, and a cutout with an opening between the base and the legs. The cutout is capable of allowing a clamp or a wrap to extend through the opening and around the motor in order to couple the baseplate to the motor.

Some embodiments of the invention provide a brush ring assembly including a brush ring, one or more brushes, a brush holder, and one or more springs. The brush holder is coupled to the brush ring and secures the brush within a brush opening. The brush holder also includes a spring anchor offset from the brush opening. The spring is in contact with the brush to urge the brush through the brush opening. The spring also includes an end leg secured by the spring anchor.

According to some embodiments, the brush ring assembly includes a brush ring, one or more brushes, a brush holder for securing the brush within a brush opening, and one or more torsion springs. The torsion spring is secured by the brush holder and includes a bent portion at a first end. The entire length of the bent portion contacts the brush to urge the brush through the brush opening.

Some embodiments of the invention provide a pump including a lower housing, a diaphragm assembly positioned adjacent to the lower housing, and an upper housing positioned adjacent to the diaphragm assembly. The upper housing includes an inlet chamber and an outlet chamber separated by a ring. The pump also includes a valve housing positioned between the upper housing and the diaphragm assembly. The valve housing encloses the inlet chamber and the outlet chamber and includes a cutout in contact with the ring. An o-ring is secured between raised outer walls of the ring by the cutout.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a diaphragm pump according to one embodiment of the invention.

FIG. 2 is a perspective view of the diaphragm pump of FIG. 1.

FIG. 3 is an exploded perspective view of a diaphragm pump according to another embodiment of the invention.

FIG. 4 is another exploded perspective view of the diaphragm pump of FIG. 3.

FIGS. 5A and 5B are rear perspective views of a valve housing with and without valves, respectively, for use with the diaphragm pump of FIG. 1 or 3.

FIGS. 6A and 6B are front perspective views of a valve housing with and without valves, respectively, for use with the diaphragm pump of FIG. 1 or 3.

FIG. 7 is a perspective view of a valve for use with the valve housing of FIGS. 5A-6B.

FIG. 8 is an exploded perspective view of a valve housing for use with a diaphragm pump according to another embodiment of the invention.

FIG. 9 is a perspective view of a diaphragm assembly for use with the diaphragm pump of FIG. 1 or 3.

FIG. 10A is a perspective view of a baseplate for use with the diaphragm pump of FIG. 1.

FIG. 10B is a perspective view of a baseplate for use with the diaphragm pump of FIG. 3.

FIG. 11 is an exploded perspective view of a motor for use with the diaphragm pump of FIG. 1 or 3.

FIGS. 12A-12C are perspective parts views of a brush ring assembly of the motor of FIG. 11.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings.

The following discussion is presented to enable a person skilled in the art to make and use embodiments of the invention. Various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the generic principles herein can be applied to other embodiments and applications without departing from embodiments of the invention. Thus, embodiments of the invention are not intended to be limited to embodiments shown, but are to be accorded the widest scope consistent with the principles and features disclosed herein. The following detailed description is to be read with reference to the figures, in which like elements in different figures have like reference numerals. The figures, which are not necessarily to scale, depict selected embodiments and are not intended to limit the scope of embodiments of the invention. Skilled artisans will recognize the examples provided herein have many useful alternatives and fall within the scope of embodiments of the invention.

FIGS. 1 and 2 illustrate a pump 10 according to one embodiment of the invention. The pump 10 can include an upper housing 12, a diaphragm assembly 14, a lower housing 16, an inlet 18, an outlet 20, a pressure switch assembly 22, and a relief valve assembly 24. The upper housing 12, the diaphragm assembly 14, and the lower housing 16 can be coupled together via fasteners 26 (e.g., screws and washers, nuts and bolts, rivets, etc.). Reference herein and in the appended claims to terms of orientation (such as upper and lower) are provided for purposes of illustration only and are not intended as limitations upon the scope of the invention. The pump 10 and various elements of the pump 10 can be oriented in any manner desired while still falling within the spirit and score of the present invention.

The pump 10, and more specifically the lower housing 16, can be coupled to a motor 28. In one embodiment, as shown in FIGS. 1 and 2, the pump 10 and the motor 28 can be coupled to a baseplate 30 via fasteners (not shown). The baseplate 30 can include legs 32 adapted to support the weight of the pump 10 and the motor 28. In another embodiment, as shown in FIGS. 3 and 4, the pump 10 and the motor 28 can be coupled to a baseplate 34 via fasteners 35. In addition, as shown in FIGS. 1 and 2, the motor 28 and the pressure switch assembly 22 can include electrical connectors 36.

The inlet 18 can be connected to an inlet fluid line (not shown) and the outlet 20 can be connected to an outlet fluid line (not shown). As shown in FIGS. 1 and 2, both the inlet 18 and the outlet 20 can be threaded or barbed and can be connected to the respective fluid lines via fittings, such as quick disconnect fittings, compression fittings, swage fittings, etc. Gaskets, o-rings, or other seals can also be included to help prevent leakage between the inlet 18 and/or the outlet 20 and their respective fittings and/or fluid lines. As shown in FIG. 3, the upper housing 12 can include an inlet chamber 38 in communication with the inlet 18 and an outlet chamber 40 in communication with the outlet 20. The inlet chamber 38 and the outlet chamber 40 can be separated by a ring 42.

As shown in FIGS. 3 and 4, the pump 10 can include a valve housing 44 positioned between the upper housing 12 and the diaphragm assembly 14. The valve housing 44 can assist in enclosing and separating the inlet chamber 38 from the outlet chamber 40. More specifically, as shown in FIG. 3, the ring 42 of the upper housing 12 can have raised outer walls 46 to engage a cutout 48 (as shown in FIG. 4) of the valve housing 44 between the raised outer walls 46 when the pump 10 is assembled. An o-ring 50 (as also shown in FIG. 4) can be set between the ring 42 and the cutout 48 to provide a water-tight seal between the inlet chamber 38 and the outlet chamber 40. The raised outer walls 46 can center and secure the valve housing 44 in place and can also prevent the valve housing 44 from wobbling during pump operation at high pressures. The raised outer walls 46 can secure the o-ring 50 in place, which can prevent the o-ring 50 from expanding outside past the ring 42 and the cutout 48 and also can greatly reduce wear on the o-ring 50.

In addition, as shown in FIG. 3, the valve housing 44 can at least partially define one or more pump chambers 52. In some embodiments, the valve housing 44 can define two, three, four (as shown in FIGS. 1-4), five (as shown in FIG. 8), or more pump chambers 52. As shown in FIGS. 5A and 5B, each pump chamber 52 can include an inlet port 54 and an outlet port 56. As shown in FIGS. 5A-5B and 6A-6B, each inlet port 54 can include an inlet valve 58 that is positioned within an inlet valve seat 60 and each outlet port 56 can include an outlet valve 62 that is positioned within an outlet valve seat 64. In one embodiment, the inlet valves 58 can face the pump chambers 52, while the outlet valves 62 can face the upper housing 12. In addition, as shown in FIG. 6B, the cutout 48 can protrude from the valve housing 44 to separate the inlet valves 58 from the outlet valves 62 on the side of the valve housing 44 that faces the upper housing 12 (e.g., to help separate incoming fluid from the inlet chamber 38 through the inlet valves 58 and outgoing fluid from the outlet valves 62 through the outlet chamber 40).

As shown in FIG. 5B, each inlet valve seat 60 can include a central inlet aperture 66 and peripheral inlet apertures 68. As shown in FIG. 6B, each outlet valve seat 64 can include a central outlet aperture 70 and peripheral outlet apertures 72. As shown in FIGS. 5A and 6A, the inlet valves 58 and the outlet valves 62 can include headed extensions 74, 76 that can be press-fitted into the respective central apertures 66, 70. In some embodiments, the inlet valves 58 and the outlet valves 62 can be disc-shaped flexible elements. In addition, each inlet valve 58 and each outlet valve 62 can include a blind hole 78 at its center on the side opposite the headed extension 74, 76, as shown in FIG. 7.

In some embodiments, as shown in FIG. 8, a valve insert 80 can be press-fitted into each blind hole 78 to secure the valve 58, 62 within the valve seat 60, 64. The use of the valve inserts 80 can prevent the valves 58, 62 from spinning or popping out of their respective central apertures 66, 70 during pump operation with high flows and/or viscosities. The valve inserts 80 can also prevent the valves 58, 62 from ballooning or rupturing at during pump operation at high pressures. In addition, the blind hole 78 can provide relief for the material of the valves 58, 62 to compress during their manufacturing process, thus preventing cracks from forming in the valves 58, 62 and failure during pump operation due to the cracks.

As shown in FIGS. 3-4 and 9, the diaphragm assembly 14 can include a diaphragm 82 with a plurality of pistons 84. Each piston 84 can correspond to a respective pump chamber 52 of the valve housing 44. The diaphragm 82 can include a single piece of resilient material with features integral with and molded into the diaphragm 82. In other embodiments of the invention, the diaphragm 82 can be constructed of multiple elements connected together, such as by fasteners, adhesive or cohesive bonding material, snap-fit connections, etc. The diaphragm 82 can include a body portion 86 lying generally in a first plane. The pistons 84 can lie generally in a second plane parallel to the first plane of the body portion 86. The diaphragm 82 can help define the pump chambers 52 and can help isolate the pump chambers 52 from one another. For example, the diaphragm 82 can include an outer lip portion 88 and an inner lip portion 90 that fit around the perimeter of each pump chamber 52 when the valve housing 44 and the diaphragm 82 are coupled together so that each pump chamber 52 is isolated from one another when the valve housing 44 is fitted against the diaphragm 82. In some embodiments, the diaphragm 82 and the valve housing 44 can include other sealing relationships to isolate the pump chambers 52.

Each piston 84 can have a corresponding convolute 92 to couple the piston 84 to the body portion 86 of the diaphragm 82. For example, each piston 84 can be co-molded to a corresponding convolute 92. The convolutes 92 can function to allow the pistons 84 to move reciprocally and with respect to the first plane of the body portion 86 without placing damaging stress upon the diaphragm 82. Each convolute 92 can include an inner perimeter portion 94 positioned closer to a center point 96 of the diaphragm 82 than an outer perimeter portion 98. The outer perimeter portion 98 of each convolute 92 can include more material than the inner perimeter portion 94. As a result, the depth of the convolute 92 at the outer perimeter portion 98 can be larger than the depth of the convolute 92 at the inner perimeter portion 94. This arrangement can provide the piston 84 with greater range of motion at the outer perimeter 98 than at the inner perimeter 94. In this configuration, a bottom surface of each convolute 92 can be oriented at an angle sloping away from the center point 96 of the diaphragm 82 and away from the second plane in which the pistons 84 lie.

Referring back to FIG. 3, the pump 10 can include a wobble plate 100 coupled to rocker arms 102. The number of rocker arms 102 can correlate to the number of pistons 54 of the diaphragm 82. The rocker arms 102 can be coupled to the pistons 84 so that the pistons 84 are actuated by movement of the wobble plate 100. The rocker arms 102 can transmit force from the center of the wobble plate 100 to locations adjacent to the pistons 84. The center of each piston 84 can be coupled to a corresponding rocker arm 102 via a fastener 104 (e.g., screw, nut and bolt set, other threaded fastener, rivet, snap-fit connection, etc.) or another coupling manner, such as by adhesive or cohesive bonding material.

Referring back to FIG. 4, the motor 28 can include a rotatable output shaft 106 that can extend through the lower housing 16. The wobble plate 100 can engage the output shaft 106 so that, as the output shaft 106 rotates, the wobble plate 100 turns and the pistons 84 are individually engaged in turn.

During operation, fluid flows into the inlet chamber 38 from the inlet 18. Movement of the diaphragm 82 by the wobble plate 100 causes pressure differences in the pump chambers 52 and can change the orientation of the inlet valves 58 and the outlet valves 62. In a first orientation, fluid flow into the pump chamber 52 from the inlet chamber 38 is permitted by the inlet valve 58 through peripheral inlet apertures 68. In a second orientation, fluid flow out of the pump chamber 52 into the outlet chamber 40 is permitted by the outlet valve 62 through peripheral outlet apertures 72. The valves 58, 62 can function as one-way check valves, preventing fluid flow in a respective opposite direction (i.e., preventing fluid flow from the pump chambers 52 to the inlet chamber 38 or from the outlet chamber 40 into the pump chambers 52). Once in the outlet chamber 40, fluid can exit through the outlet 20. Pressure in the outlet chamber 40 can be monitored by the pressure switch assembly 22 and, in some embodiments, the motor 28 can be operated based on the monitored pressure. In addition, if pressure in the inlet chamber 38 exceeds a threshold, the relief valve assembly 24 can allow fluid to flow directly from the inlet chamber 38 to the outlet chamber 40 until the pressure in the inlet chamber 38 falls below the threshold.

FIG. 10A illustrates the baseplate 30 of FIGS. 1-2. FIG. 10B illustrates the baseplate 34 of FIGS. 3-4. The baseplates 30/34 can be coupled to the motor 28 by fasteners 35 through mounting holes 107. Also, the baseplates 30/34 can include leg holes 108 extending through the legs 32 to accommodate mounting of the pump 10 and the motor 28 to a surface via the legs 32, the leg holes 108, and fasteners (not shown). As shown in FIGS. 3-4 and 10B, the baseplate 34 can include removable cushions 110 positioned on or through the legs 32. The cushions 110 can be constructed of a resilient material (e.g., rubber, urethane, etc.) so that vibration from the pump 10 to the surrounding environment can be reduced.

As shown in FIG. 10B, the baseplate 34 can have an elongated base 112 that is in contact with the motor 28, thus permitting a large surface area for heat dissipation from the motor 28 during operation. For example, the base 112 can be curved in order to maintain contact around a portion of the circumference of the motor 28. The base 112 can also include a cutout 114. The cutout 114 can provide an opening 113 between the base 112 and the legs 32 and can include rounded flanges 115 that correspond with the shape of the motor 28. More specifically, the rounded flanges 115 can extend from the opening 113 around a portion of the circumference of the motor 28. The cutout 114 can allow the option of coupling the baseplate 34 to the motor 28 with drive clamps or tie wraps (e.g., through the opening 113 and around the motor 28, the flanges 115, and the base 112). In some embodiments of the invention, this option can be used in conjunction with the mounting holes 107 and the fasteners 35. In other embodiments, this option can be used instead of the mounting holes 107 and the fasteners 35. Also, in some embodiments, the cutout 114 may only include the opening 113 without the flanges 115.

In some embodiments, as shown in FIG. 11, the motor 28 can include a first o-ring 116, a motor housing 118, internal magnets 120, an armature 122, a commutator 124, bearings and washers 126, a second o-ring 128, brush springs 130, a brush ring assembly 132, a rear endbell or shroud 134, and fasteners 136. The fasteners 136 can extend from the rear endbell 134, through the motor housing 118, to the lower housing 16 to couple the motor 28 to the lower housing 16. In addition, the brush ring assembly 132 can include a brush ring 138, one or more brushes 140, brush holders 142, capacitors 144, and a thermal protector 146. As shown in FIG. 11, the motor 28 is a two-brush, direct current (DC) motor. In some embodiments, the motor 28 can include more than two brushes 140. On the brush ring assembly 132, the electrical connections 36 (e.g., positive and negative electrical connections) can each be connected to one of the two brushes 140 via brush leads 148 (e.g., as shown in FIG. 12A, through the thermal protector 146 or the capacitors 144). The brushes 140 can come in contact with the commutator 124, causing current flow through the armature 122 and magnetic field generation. As a result of the magnetic field generated by the armature 122 and the adjacent internal magnets 120, the armature 122 rotates within the motor housing 118, also causing rotation of the output shaft 106. In addition, in some embodiments, the motor 28 can be an alternating current (AC) rectified motor (e.g., the motor 28 can rectify alternating current input to provide direct current to the brushes 140).

FIG. 12A illustrates a partial view of the brush ring assembly 132, including the two brushes 140, the brush holders 142, and the brush springs 130. As shown in FIGS. 12A and 12B, the brush springs 130 can be torsion springs, each including an urging end portion 150 and an opposite end leg portion 152. As shown in FIGS. 12A and 12C, each brush holder 142 can include a mounting portion 154 for mounting the brush holder 142 to the brush ring 138 (e.g., via rivets 156), a brush opening or through hole 157 to accommodate the brush 140, a brush lead track or slit 158 to accommodate the brush lead 148, a spring wire track or slit 160 to accommodate the urging end portion 150 of the brush spring 130, a spring holder 162 to support the brush spring 130, and a spring anchor 164 to secure the end leg 152 of the brush spring 130.

As shown in FIG. 12A, the urging end portion 150 of the brush spring 130 can extend through the spring wire track 160 and press against a top portion 166 of the brush 140. As a result, the brush spring 130 presses the brush 140 against the commutator 124, ensuring a solid connection between the brush 140 and the rotating commutator 124. The brush spring 130 can continue to urge the brush 140 downward against the commutator 124 despite continuous wear on the brush 140 (e.g., due to the brush 140 being in constant contact with the rotating commutator 124). As shown in FIG. 12B, the urging end portion 150 can include a bent portion 168. The entire length of the bent portion 168 (i.e., between the edge 170 of the brush spring 130 and a bend 172 near the edge of the brush spring 130, as shown in FIG. 12B) can press against the brush 140 to urge the brush 140 downward, in comparison to a single end point or edge point of conventional brush springs. The bent portion 168 can provide a line contact against the brush 140 (e.g., in comparison to conventional point contacts), ensuring that the brush spring 130 continues to urge the brush 140 downward as either component wears. The bent portion 168 can provide a longer life for the brush spring 130, since wear will occur along the entire length of the bent portion 168 less quickly than on an end point contact of conventional brush springs.

Conventionally, spring anchors that are integral with a brush holder will position the spring end leg over the top of the brush opening. As a result, the initial length of the brush is limited by the positioning of the spring end leg. In some embodiments, as shown in FIG. 12C, the spring anchor 164 can be a hook offset from the brush opening 157 (e.g., in front of the brush opening 157). More specifically, in one embodiment, the spring anchor 164 can be positioned opposite from the mounting portion 154 of the brush holder 142, or further away from the brush ring 138 than the spring wire track 160. The unimpeded brush opening 157 can thus permit longer brushes 140, and as a result, longer life of the motor 28 before brush replacement is necessary.

It will be appreciated by those skilled in the art that while the invention has been described above in connection with particular embodiments and examples, the invention is not necessarily so limited, and that numerous other embodiments, examples, uses, modifications and departures from the embodiments, examples and uses are intended to be encompassed by the claims attached hereto. The entire disclosure of each patent and publication cited herein is incorporated by reference, as if each such patent or publication were individually incorporated by reference herein. Various features and advantages of the invention are set forth in the following claims. 

1. A pump assembly comprising: a pump; a motor coupled to the pump; and a baseplate that extends across a length of the motor and includes a base, legs, and a cutout with an opening between the base and the legs, the cutout capable of allowing one of a clamp and a wrap to extend through the opening and around the motor in order to couple the baseplate to the motor.
 2. The pump assembly of claim 1, wherein the cutout further includes rounded flanges that extend from the opening around a portion of the circumference of the motor.
 3. The pump assembly of claim 1, and further comprising mounting holes through the base in order to couple the baseplate to the motor with fasteners.
 4. The pump assembly of claim 1, and further comprising removable cushions coupled to the legs.
 5. The pump assembly of claim 1, wherein the base is curved in order to maintain contact around a portion of the circumference of the motor.
 6. The pump assembly of claim 1, and further comprising leg holes extending through the legs in order to allow coupling of the baseplate to a surface with fasteners.
 7. A brush ring assembly comprising: a brush ring; at least one brush; a brush holder coupled to the brush ring and securing the at least one brush within a brush opening, the brush holder including a spring anchor positioned offset from the brush opening; and at least one spring in contact with the at least one brush to urge the at least one brush through the brush opening, the at least one spring including an end leg secured by the spring anchor.
 8. The brush ring assembly of claim 7, wherein the brush holder includes a mounting portion, wherein the brush holder is coupled to the brush ring by the mounting portion.
 9. The brush ring assembly of claim 8, wherein the spring anchor is positioned on an opposite side of the brush holder than the mounting portion.
 10. The brush ring assembly of claim 7, wherein the brush holder includes a spring wire track to allow the spring to extend into the brush opening and contact the at least one brush, wherein the spring anchor is positioned farther from the brush ring than the spring wire track.
 11. The brush ring assembly of claim 7, wherein the brush holder includes a spring holder to support the at least one spring.
 12. A brush ring assembly comprising: a brush ring; at least one brush; a brush holder coupled to the brush ring and securing the at least one brush within a brush opening; and at least one torsion spring secured by the brush holder and including a bent portion at a first end, an entire length of the bent portion contacting the at least one brush to urge the at least one brush through the brush opening.
 13. The brush ring assembly of claim 12, wherein the brush holder includes a spring wire track and the first end of the at least one torsion spring extends through the spring wire track so that the bent portion contacts the at least one brush.
 14. The brush ring assembly of claim 12, wherein the at least one torsion spring includes an end leg portion along an opposite, second end, wherein the brush holder includes a spring anchor to secure the end leg portion.
 15. The brush ring assembly of claim 12, wherein the entire length of the bent portion spans from a bend near the first end to an edge of the first end.
 16. A pump comprising: a lower housing; a diaphragm assembly positioned adjacent to the lower housing; an upper housing positioned adjacent to the diaphragm assembly and including an inlet chamber and an outlet chamber separated by a ring; a valve housing positioned between the upper housing and the diaphragm assembly and enclosing the inlet chamber and the outlet chamber, the valve housing including a cutout in contact with the ring, the ring including raised outer walls to receive the cutout; and an o-ring positioned between the raised outer walls of the ring and secured between the raised outer walls by the cutout.
 17. The pump of claim 16, wherein the cutout protrudes from the valve housing and extends into the ring between the raised outer walls.
 18. The pump of claim 16, and further comprising an inlet in fluid communication with the inlet chamber and an outlet in fluid communication with the outlet chamber.
 19. The pump of claim 16, wherein the cutout separates a plurality of inlet valves from a plurality of outlet valves on the valve housing.
 20. The pump of claim 16, and further comprising a diaphragm secured by the diaphragm assembly, wherein movement of the diaphragm controls the flow of fluid from the inlet chamber to the outlet chamber. 